/*
 * Created on 14-Feb-2005
 * Created by Paul Gardner
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

package org.gudy.azureus2.core3.tracker.client.impl.bt;

import java.net.URL;

import org.gudy.azureus2.core3.internat.MessageText;
import org.gudy.azureus2.core3.torrent.TOTorrent;
import org.gudy.azureus2.core3.tracker.client.TRTrackerAnnouncer;
import org.gudy.azureus2.core3.tracker.client.TRTrackerScraperResponse;
import org.gudy.azureus2.core3.tracker.client.impl.TRTrackerScraperImpl;
import org.gudy.azureus2.core3.tracker.client.impl.TRTrackerScraperResponseImpl;
import org.gudy.azureus2.core3.util.AEMonitor;
import org.gudy.azureus2.core3.util.TorrentUtils;
import org.gudy.azureus2.plugins.download.DownloadScrapeResult;

/**
 * @author parg
 * 
 */

public class TRTrackerBTScraperImpl {
    protected static TRTrackerBTScraperImpl singleton;
    protected static AEMonitor class_mon = new AEMonitor("TRTrackerBTScraper");

    private TRTrackerScraperImpl scraper;
    private TrackerChecker tracker_checker;

    public static TRTrackerBTScraperImpl create(TRTrackerScraperImpl _scraper) {
        try {
            class_mon.enter();

            if (singleton == null) {

                singleton = new TRTrackerBTScraperImpl(_scraper);
            }

            return (singleton);

        } finally {

            class_mon.exit();
        }
    }

    protected TRTrackerBTScraperImpl(TRTrackerScraperImpl _scraper) {
        scraper = _scraper;

        tracker_checker = new TrackerChecker(this);
    }

    protected TRTrackerScraperImpl getScraper() {
        return (scraper);
    }

    public void setScrape(TOTorrent torrent, URL url, DownloadScrapeResult result) {
        if (torrent != null && result != null) {

            TRTrackerScraperResponseImpl resp = tracker_checker.getHashData(torrent, url);

            URL result_url = result.getURL();

            boolean update_is_dht = TorrentUtils.isDecentralised(result_url);

            // only override details if underlying scrape is failing or this is an update
            // to an existing dht-backup result

            if (resp != null && (resp.getStatus() == TRTrackerScraperResponse.ST_ERROR || (resp.isDHTBackup() && update_is_dht))) {

                resp.setDHTBackup(update_is_dht);

                resp.setScrapeStartTime(result.getScrapeStartTime());

                // leave nextScrapeStartTime alone as we still want the existing
                // scraping mechanism to kick in and check the torrent's tracker

                resp.setStatus(result.getResponseType() == DownloadScrapeResult.RT_SUCCESS ? TRTrackerScraperResponse.ST_ONLINE
                        : TRTrackerScraperResponse.ST_ERROR, result.getStatus() + " ("
                        + (update_is_dht ? MessageText.getString("dht.backup.only") : (result_url == null ? "<null>" : result_url.getHost())) + ")");

                // call this last before dispatching listeners as it does another dispatch by itself ~~
                resp.setSeedsPeers(result.getSeedCount(), result.getNonSeedCount());

                scraper.scrapeReceived(resp);
            }
        }
    }

    public TRTrackerScraperResponse scrape(TOTorrent torrent, URL target_url, boolean force) {
        if (torrent == null) {

            return null;
        }

        if (force) {

            tracker_checker.syncUpdate(torrent, target_url);
        }

        TRTrackerScraperResponse res = tracker_checker.getHashData(torrent, target_url);

        // System.out.println( "scrape: " + torrent + " -> " + (res==null?"null":""+res.getSeeds()));

        return (res);
    }

    public TRTrackerScraperResponse peekScrape(TOTorrent torrent, URL target_url) {
        if (torrent == null) {

            return null;
        }

        TRTrackerScraperResponse res = tracker_checker.peekHashData(torrent, target_url);

        return (res);
    }

    public TRTrackerScraperResponse scrape(TRTrackerAnnouncer tracker_client) {
        TRTrackerScraperResponse res = tracker_checker.getHashData(tracker_client);

        // System.out.println( "scrape: " + tracker_client + " -> " + (res==null?"null":""+res.getSeeds()));

        return (res);
    }

    public void remove(TOTorrent torrent) {
        tracker_checker.removeHash(torrent);
    }
}
